Field of the Invention
This invention relates to the art of installing devices such as ground anchors in the ground and particularly deals with coupled drive rods or gads and methods for installing ground anchors wherein a string of drive rods are joined in end to end relation by devices which are not subjected to compression loads, but which hold the rods together in end to end relation under tension loads.
Heretofore drive rods or gads for installing ground anchors and the like have been coupled in end to end relation by internally threaded sleeves or couplings which were unable to hold the rods in abutting relation during impact blows for driving ground anchors or the like into the ground. These sleeves or couplings soon became loose and were forced to carry the compression loads of the impact blows. In effect, the impact blows were delivered through the threads of the couplers or sleeves resulting in energy losses, high temperatures, and early failures.
It would therefore be an improvement in this art to install ground anchors and the like through hammer impacted end to end coupled drive rods or gads without compressively loading any coupling devices while ensuring end to end abutments of the drive rod rods during impact.
It would be a further improvement in this art to provide a method of installing ground anchors of the type driven upright or endwise into the ground to a desired depth by a string of coupled drive rods or gads and then rotated flatwise into a locked position in the ground by a pull member wherein the couplings of the drive rods string are never subjected to impact blows or compression loads but support tension loads to retract the string from the ground.
As used herein, the terms "drive rods" and "gads" include structures driven into the ground especially for installing ground anchors.